I have a GCC spec G35 and over here there's no Journey, Sport or X. theres only one option, a RWD G35 with paddle shifters, 5AT, wood interior, Journey body kit, Sport wheels/tires with corner indicators and F/R park sensors. a couple other people told me we have the VLSD and suspension from the sport. i tried doing a quick donut and I can see that both wheels spin and its pretty easy to do. Does that mean i have a VLSD? and what about the springs? How can i know what's under there?

Thanks

 

i don't think there's a clear cut way of determining if you have a limited slip by doing donuts,

one way is to lift up the rear with both wheels off the ground, have two people perform a check, on one side, spin the wheel one way (like going forward) and the other wheel, spin it the other way (like going backwards),

with an open diff it should easily spin, with a limited slip, it won't spin, or it's very very difficult to spin

i believe both springs are the same between sport and non sport, i don't know, but after market is better anyways...

 

I would be interested in finding this out too, as I'm GCC Spec here. I didn't know we have the same springs as the sport (if they're different) but would you know if we have the sports sway bars as well? as the sports ones are larger than the Journey ones???

 

I always thought our VLSD was an open diff design?

 

my knowledge is limited, but i do know that open acts and spins freely, and any other type of lsd won't

vlsd is just a, some would consider, weaker type of lsd, special fluid encased inside the pumpkin that can't be replaced and will wear out over time, which will turn it basically into an open diff.
Note: you still need to replace the gear oil/differential oil on normal maintenance interval, vlsd fluid is different

aftermarket types are better, clutch/mechanical, they engage better, and most of those are rebuildable

 

I wouldn't say a Viscous LSD is weaker... it's just a simpler design... and is probably more suitable for the average driver, although they do tend to lose more power than other types of lsds, and fail more.

 

The wheels in the air probably isn't going to work with a viscous. I'm not sure you could spin the wheel fast enough to heat the fluid into locking the other wheel. Have you looked under the car at the rear differential? If the different rear ends requires different fluid, I would think it would be marked on the pumpkin.

 

unless they've changed how they make vlsd, fluids internally within vlsd cannot be replaced, but the gear oil surrounding the internal casing should be replaced just like any differential oil flush

i've held an actual vlsd unit from an old j30 and an open diff from a 240sx,
open diff, you can spin opposite directions freely
vlsd, can't spin in opposite direction, it locks

 

I have a viscous center diff on my DSM. I can spin the front or rear easily with all four in the air. Same with my rear end on that car. How do I know they are there? 1.6 60' on crappy Falken's is all the proof I need.

Edit: Yes, the Viscous coupler is self contained so the fluid surounding it would not be different than a non vlsd.

 

if you do have any type of lsd, i highly doubt you can spin your left rear forward and your right rear backwards at the same time, (manually, with the rear end in the air)

i'm not talking about front spinning and rear spinning, that's different

awd/4wd is different

OP is referring to rwd only

 

That's the nice thing about my Mitsu, LSD is on the pumpkin

I can spin the left rear and the right rear will spin the opposite direction. This is with no resistance on the other wheel. No perhpas if someone were to apply some pressure, it would possibly lock up. I still doubt that a VISCOUS type differential will heat up enough from hand turning to engauge.

 

why not....

 

A viscous differential has plates inside it and fluid. When the plates start to spin at different speeds, the fluid solidifies which locks the plates. This requires heat. Hand turning a wheel will produce how much speed...1...2mph at best?

Here, from wikipediea:
The viscous type is generally simpler, and relies on the properties of a dilatant fluid - that is, one which thickens when subject to shear. Silicone-based oils are often used. Here, a cylindrical chamber of fluid filled with a stack of perforated discs rotates with the normal motion of the output shafts. The inside surface of the chamber is coupled to one of the driveshafts, and the outside coupled to the differential carrier. Half of the discs are connected to the inner, the other half to the outer, alternating inner/outer in the stack. Differential motion forces the interlocked (though untouching) discs to move through the fluid against each other. The greater the relative speed of the discs, the more resistance the fluid will put up to oppose this motion. In contrast to the mechanical type, the limiting action is much softer and more proportional to the slip, and so is easier to cope with for the average driver.

 

well, from first hand experience, i can tell you with a working j30 vlsd, you cannot spin it freely (opposite directions) like you can with an open diff... you can, but it takes alot of brute force

 

Interesting. I'm sure there are different fluids used in viscous couplings that react faster/slower. Perhaps the J30 reacts faster?